1. Field of the Invention
The present invention relates to a surgical device for use in blunt tissue elevation and/or dissection such as in cranial, spine, cervical, abdominal, thoracic, lumbar, endoscopic, laparoscopic, and other types of surgery.
2. Description of the Related Art
In many types of surgery it is necessary to remove or displace tissue in order to perform a procedure. Often, this is to improve a surgeon's vision in an area of interest where more delicate operations need to be performed, or may be to remove tissue which is in the way for a procedure as it either prevents the surgeon from accessing the area of interest with the tools they need to operate on it, or inhibits the application of a prosthetic or other surgical device. One of the more common types of surgery where removal of tissue is necessary is in implantation where it is often necessary to remove tissue from a bone so an artificial device, such as a support plate, can be attached. Removing the tissue provides for a stronger safer attachment and generally can result in an improved surgical outcome.
Depending on the nature of the tissue to be removed and its location, various different types of tools are desirable. The most common type of surgical removal tool is undoubtedly a sharp device such as a scalpel, blade, saw or drill. These types of devices are necessary for virtually any type of surgery to be performed as they allow the surgeon to cut through what would otherwise be a seamless body structure. In many situations, however, they are preferably not used as should the cutting instrument slip slightly, a very dangerous situation could occur. When a surgeon is working near essential blood vessels, organs, or other sensitive structures, the slightest misplacement or deviation of a sharp device can result in potentially traumatic injury or death.
The situation can be particularly dangerous if the surgeon is working on the spine or other central nervous system component. While an inadvertent cut to a blood vessel could create a potentially dangerous situation, blood vessels can often be repaired without lasting injury. A severed spinal cord, however, often cannot be repaired even with the most advanced procedures currently known. Because of these and other issues, it is therefore desirable that a surgeon use an instrument when working near the spinal cord or similar sensitive structures which, if it were to inadvertently contact nearby tissue, would have a decreased possibility of causing injury.
One such way to avoid this type of injury is to utilize a tool which is suitable for separating two types of matter along an existing seam or connection, but is generally unsuitable for “cutting” into seamless matter. This is often referred to as a blunt dissection instrument. Blunt dissection generally allows for tissues to be dissected atraumatically by simply separating the tissue along existing seams or natural planes. That is, the tool separates along natural separations, conjunctions, or faults, without the tool being able to create a new seam on its on. This type of instrument facilitates in surgical exposure and tissue retraction both because of reducing danger to neighboring tissue, and reducing trauma from manmade separation.
While blunt dissection is a useful medical practice, the tools for blunt dissection are generally ad-hoc and often ill-suited for the task. Current practice in blunt dissection generally involves using a makeshift device which is assembled in the operating room and provides the surgeon with a temporary support for holding a small blunt dissection pad having a relatively rough surface. Generally, this makeshift device consists of a traditional Kelly clamp (locking clamp) clamping a small blunt dissection pad commonly called a cottonoid, between its jaws. A “cottonoid” is a small, rolled piece of gauze commonly used in surgical procedures for a variety of activities. The cottonoid has a relatively rough surface which is capable of grasping tissue and supporting it to separate the tissue from adjoining tissue. This structure is generally unable to damage an intact organ, blood vessel, or similar structure as the cottonoid simply cannot grip tissue with sufficient force to separate structures without an existing seam, and is generally incapable of generating a new seam or separation on its own.
This makeshift device is unsuitable for the desired task of blunt dissection in many cases and can present dangers when used for such. In the first instance, the length of the Kelly clamp arm and handle necessarily limit the device to procedures relatively close to the location of the surgeon's hands. The structure of a clamp widens quite quickly to enable the clamp to be used for its principle purpose of clamping. The use of the device as a holders, therefore, is often relatively difficult and creates a less than ideal design. Further, sufficient depth of tissue dissection is often not possible with such a device and adequate exposure and visibility is therefore often difficult, if not impossible, because the device is held by the palm of the hand and lacks appropriate length and shape to perform the procedure.
Furthermore, a Kelly clamp is liable to become unlocked during a dissection and release the cottonoid into the patient, where it would need to be retrieved from a potentially sensitive area, as Kelly clamps are generally designed for relatively simple release. Finally, the Kelly clamp device is individually created by a surgical assistant and if the Kelly clamp is not loaded correctly with the cottonoid, or even if it is loaded differently than a surgeon was expecting, the metal tips of the Kelly clamp can come into unintentional contact with the surgical area. This contact can be adverse as the metal tips can act as a sharp dissection instrument when blunt dissection was intended, thus leading to unanticipated tissue injury and poor wound healing. This contact can also occur when the surgeon is least expecting it which can lead to an increased likelihood of injury.
To try and deal with some of the problems of a makeshift tool created from a Kelly clamp, disposable cottonoid devices designed principally for homeostasis are also sometimes used as endoscopic and laparoscopic dissectors. While they can resolve some of the concerns from the Kelly clamp device, these devices still have many of the same problems of the Kelly clamp improvised device such as a lack of sufficient length and a design intended for a different purpose. Further, these disposable cottonoid devices are often weak and can break or bend preventing them from being particularly useful in dissection as they are unable to provide sufficient separation force.